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991.
992.
Oni Yuliarti Lara Matia‐Merino Kelvin T. Goh John Mawson Charles Brennan 《International Journal of Food Science & Technology》2012,47(3):633-639
Pectin was extracted from gold kiwifruit by four commercial enzyme preparations (Celluclast 1.5 L, Cytolase CL, Cellulyve TR 400 and NS33048). The chosen enzymes were used either in single or in combination, with and without protease addition. The recovered pectin was characterised and compared for the yield, total nonstarch polysaccharide and neutral sugar composition, protein and ash, pectin, molecular weight distribution and the viscosity. Results indicated that enzyme‐extracted gold kiwifruit pectin was rich in galacturonic acid. Purified pectin yield, and their physicochemical composition and rheological property (viscosity), was significantly affected by the type of enzyme used. The pectin extracted by Celluclast 1.5 L demonstrated to be the most viscous and recorded the highest in molecular weight (Mw) (1.65 × 106 g mol–1) compared with the other extracts. The extract Mw and their distribution were discussed and related to their viscosity behaviour. 相似文献
993.
Penicillium roqueforti grows and sporulates during the ripening period of blue cheeses and it is responsible for the typical blue cheese flavour formation. However, the sporulation (blue veins) is taking place in a fraction of the total mass and the cheese matrix is highly heterogeneous. The aroma profiles regarding the three different sections of Stilton cheese, blue veins outer crust and white core, were studied using solvent extraction GC–MS, a headspace GC–MS technique (SPME GC–MS) and direct headspace analysis (APCI–MS). Cheeses from different dairies were analysed, allowing the question of how similar are different batches of cheese from different dairies. 相似文献
994.
This paper studies the effects of quartz on bioleaching of chalcopyrite by Acidithiobacillus ferrooxidans, LD-1 through shaking flask experiments. The results showed that quartz concentration can affect the copper extraction. After 32 days, copper extraction of the leaching system at 50 g L−1 quartz concentration increased by about 20%, compared with that of the leaching system without quartz. XRD analysis showed that the amounts of jarosite on the chalcopyrite surface may reduce by the mechanical friction action between fine particles of quartz and chalcopyrite. The analysis of SEM indicated that the surfaces of chalcopyrite particles were eroded by different degrees and the degrees of change were the same as the effects of quartz concentration on copper extraction. 相似文献
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《Food Reviews International》2013,29(1):131-151
Abstract Solid‐phase extraction (SPE) is a rapid and sensitive sample preparation technique whose use has increased considerably within the last decade. This emerging technology has successfully replaced many tedious conventional methods of isolation and extraction of various chemicals in food, environmental, pharmaceutical, and biological samples. Sample preparation and concentration via SPE can be achieved in a one‐step extraction, and the methodology is appropriate for isolating trace amounts of chemical compounds from complex matrices. This paper gives an overview on the use of SPE as a sample preparation tool for the isolation of flavor compounds and chemical residues in food. Applying SPE in the areas of food science and agriculture will be valuable in assuring the safety and quality of our food products. 相似文献
999.
Pornanong Aramwit Sorada Kanokpanont Titpawan Nakpheng Teerapol Srichana 《International journal of molecular sciences》2010,11(5):2200-2211
Silk sericin (SS) can accelerate cell proliferation and attachment; however, SS can be extracted by various methods, which result in SS exhibiting different physical and biological properties. We found that SS produced from various extraction methods has different molecular weights, zeta potential, particle size and amino acid content. The MTT assay indicated that SS from all extraction methods had no toxicity to mouse fibroblast cells at concentrations up to 40 μg/mL after 24 h incubation, but SS obtained from some extraction methods can be toxic at higher concentrations. Heat-degraded SS was the least toxic to cells and activated the highest collagen production, while urea-extracted SS showed the lowest cell viability and collagen production. SS from urea extraction was severely harmful to cells at concentrations higher than 100 μg/mL. SS from all extraction methods could still promote collagen production in a concentration-dependent manner, even at high concentrations that are toxic to cells. 相似文献
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